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<div class="refentry">
<a name="gst-plugins-bad-plugins-webrtcdsp"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle"><a name="gst-plugins-bad-plugins-webrtcdsp.top_of_page"></a>webrtcdsp</span></h2>
<p>webrtcdsp — Audio Filter using WebRTC Audio Processing library</p>
</td>
<td class="gallery_image" valign="top" align="right"></td>
</tr></table></div>
<div class="refsect1">
<a name="gst-plugins-bad-plugins-webrtcdsp.properties"></a><h2>Properties</h2>
<div class="informaltable"><table class="informaltable" border="0">
<colgroup>
<col width="150px" class="properties_type">
<col width="300px" class="properties_name">
<col width="200px" class="properties_flags">
</colgroup>
<tbody>
<tr>
<td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp--echo-cancel" title="The “echo-cancel” property">echo-cancel</a></td>
<td class="property_flags">Read / Write / Construct</td>
</tr>
<tr>
<td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp--experimental-agc" title="The “experimental-agc” property">experimental-agc</a></td>
<td class="property_flags">Read / Write / Construct</td>
</tr>
<tr>
<td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp--extended-filter" title="The “extended-filter” property">extended-filter</a></td>
<td class="property_flags">Read / Write / Construct</td>
</tr>
<tr>
<td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp--gain-control" title="The “gain-control” property">gain-control</a></td>
<td class="property_flags">Read / Write / Construct</td>
</tr>
<tr>
<td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp--high-pass-filter" title="The “high-pass-filter” property">high-pass-filter</a></td>
<td class="property_flags">Read / Write / Construct</td>
</tr>
<tr>
<td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp--noise-suppression" title="The “noise-suppression” property">noise-suppression</a></td>
<td class="property_flags">Read / Write / Construct</td>
</tr>
<tr>
<td class="property_type">
<a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *</td>
<td class="property_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp--probe" title="The “probe” property">probe</a></td>
<td class="property_flags">Read / Write / Construct</td>
</tr>
<tr>
<td class="property_type"><span class="type">GstWebrtcEchoSuppressionLevel</span></td>
<td class="property_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp--echo-suppression-level" title="The “echo-suppression-level” property">echo-suppression-level</a></td>
<td class="property_flags">Read / Write / Construct</td>
</tr>
<tr>
<td class="property_type"><span class="type">GstWebrtcNoiseSuppressionLevel</span></td>
<td class="property_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp--noise-suppression-level" title="The “noise-suppression-level” property">noise-suppression-level</a></td>
<td class="property_flags">Read / Write / Construct</td>
</tr>
<tr>
<td class="property_type"><a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp--delay-agnostic" title="The “delay-agnostic” property">delay-agnostic</a></td>
<td class="property_flags">Read / Write / Construct</td>
</tr>
</tbody>
</table></div>
</div>
<a name="GstWebrtcDsp"></a><div class="refsect1">
<a name="gst-plugins-bad-plugins-webrtcdsp.other"></a><h2>Types and Values</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="name">
<col class="description">
</colgroup>
<tbody><tr>
<td class="datatype_keyword"> </td>
<td class="function_name"><a class="link" href="gst-plugins-bad-plugins-webrtcdsp.html#GstWebrtcDsp-struct" title="GstWebrtcDsp">GstWebrtcDsp</a></td>
</tr></tbody>
</table></div>
</div>
<div class="refsect1">
<a name="gst-plugins-bad-plugins-webrtcdsp.object-hierarchy"></a><h2>Object Hierarchy</h2>
<pre class="screen">    <a href="/usr/share/gtk-doc/html/gobjectgobject-The-Base-Object-Type.html#GObject-struct">GObject</a>
    <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gobjectgobject-The-Base-Object-Type.html#GInitiallyUnowned">GInitiallyUnowned</a>
        <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0GstObject.html#GstObject-struct">GstObject</a>
            <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-1.0GstElement.html#GstElement-struct">GstElement</a>
                <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gstreamer-libs-1.0GstBaseTransform.html#GstBaseTransform-struct">GstBaseTransform</a>
                    <span class="lineart">╰──</span> <a href="/usr/share/gtk-doc/html/gst-plugins-base-libs-1.0gst-plugins-base-libs-gstaudiofilter.html#GstAudioFilter-struct">GstAudioFilter</a>
                        <span class="lineart">╰──</span> GstWebrtcDsp
</pre>
</div>
<div class="refsect1">
<a name="gst-plugins-bad-plugins-webrtcdsp.description"></a><h2>Description</h2>
<p>A voice enhancement filter based on WebRTC Audio Processing library. This
library provides a whide variety of enhancement algorithms. This element
tries to enable as much as possible. The currently enabled enhancements are
High Pass Filter, Echo Canceller, Noise Suppression, Automatic Gain Control,
and some extended filters.</p>
<p>While webrtcdsp element can be used alone, there is an exception for the
echo canceller. The audio canceller need to be aware of the far end streams
that are played to loud speakers. For this, you must place a webrtcechoprobe
element at that far end. Note that the sample rate must match between
webrtcdsp and the webrtechoprobe. Though, the number of channels can differ.
The probe is found by the DSP element using it's object name. By default,
webrtcdsp looks for webrtcechoprobe0, which means it just work if you have
a single probe and DSP.</p>
<p>The probe can only be used within the same top level GstPipeline.
Additonally, to simplify the code, the probe element must be created
before the DSP sink pad is activated. It does not need to be in any
particular state and does not even need to be added to the pipeline yet.</p>
<div class="refsect2">
<a name="id-1.2.134.7.5"></a><h3>Example launch line</h3>
<p>As a conveniance, the echo canceller can be tested using an echo loop. In
this configuration, one would expect a single echo to be heard.</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1</pre></td>
        <td class="listing_code"><pre class="programlisting">gst<span class="gtkdoc opt">-</span>launch<span class="gtkdoc opt">-</span><span class="number">1.0</span> pulsesrc <span class="gtkdoc opt">!</span> webrtcdsp <span class="gtkdoc opt">!</span> webrtcechoprobe <span class="gtkdoc opt">!</span> pulsesink</pre></td>
      </tr>
    </tbody>
  </table>
</div>

<p></p>
<p>In real environment, you'll place the probe before the playback, but only
process the far end streams. The DSP should be placed as close as possible
to the audio capture. The following pipeline is astracted and does not
represent a real pipeline.</p>
<div class="informalexample">
  <table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
    <tbody>
      <tr>
        <td class="listing_lines" align="right"><pre>1
2</pre></td>
        <td class="listing_code"><pre class="programlisting">gst<span class="gtkdoc opt">-</span>launch<span class="gtkdoc opt">-</span><span class="number">1.0</span> far<span class="gtkdoc opt">-</span>end<span class="gtkdoc opt">-</span>src <span class="gtkdoc opt">!</span> audio<span class="gtkdoc opt">/</span>x<span class="gtkdoc opt">-</span>raw<span class="gtkdoc opt">,</span>rate<span class="gtkdoc opt">=</span><span class="number">48000</span> <span class="gtkdoc opt">!</span> webrtcechoprobe <span class="gtkdoc opt">!</span> pulsesink \
               pulsesrc <span class="gtkdoc opt">!</span> audio<span class="gtkdoc opt">/</span>x<span class="gtkdoc opt">-</span>raw<span class="gtkdoc opt">,</span>rate<span class="gtkdoc opt">=</span><span class="number">48000</span> <span class="gtkdoc opt">!</span> webrtcdsp <span class="gtkdoc opt">!</span> far<span class="gtkdoc opt">-</span>end<span class="gtkdoc opt">-</span>sink</pre></td>
      </tr>
    </tbody>
  </table>
</div>

<p></p>
</div>
<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<div class="refsect2">
<a name="id-1.2.134.7.6.1"></a><h3>Element Information</h3>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term">plugin</span></p></td>
<td>
            <a class="link" href="gst-plugins-bad-plugins-plugin-webrtcdsp.html#plugin-webrtcdsp">webrtcdsp</a>
          </td>
</tr>
<tr>
<td><p><span class="term">author</span></p></td>
<td>Nicolas Dufresne &lt;nicolas.dufresne@collabora.com&gt;</td>
</tr>
<tr>
<td><p><span class="term">class</span></p></td>
<td>Generic/Audio</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="id-1.2.134.7.6.2"></a><h3>Element Pads</h3>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term">name</span></p></td>
<td>sink</td>
</tr>
<tr>
<td><p><span class="term">direction</span></p></td>
<td>sink</td>
</tr>
<tr>
<td><p><span class="term">presence</span></p></td>
<td>always</td>
</tr>
<tr>
<td><p><span class="term">details</span></p></td>
<td>audio/x-raw, format=(string)S16LE, layout=(string)interleaved, rate=(int){ 48000, 32000, 16000, 8000 }, channels=(int)[ 1, 2147483647 ]</td>
</tr>
</tbody>
</table></div>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term">name</span></p></td>
<td>src</td>
</tr>
<tr>
<td><p><span class="term">direction</span></p></td>
<td>source</td>
</tr>
<tr>
<td><p><span class="term">presence</span></p></td>
<td>always</td>
</tr>
<tr>
<td><p><span class="term">details</span></p></td>
<td>audio/x-raw, format=(string)S16LE, layout=(string)interleaved, rate=(int){ 48000, 32000, 16000, 8000 }, channels=(int)[ 1, 2147483647 ]</td>
</tr>
</tbody>
</table></div>
</div>
</div>
</div>
<div class="refsect1">
<a name="gst-plugins-bad-plugins-webrtcdsp.functions_details"></a><h2>Functions</h2>
<p></p>
</div>
<div class="refsect1">
<a name="gst-plugins-bad-plugins-webrtcdsp.other_details"></a><h2>Types and Values</h2>
<div class="refsect2">
<a name="GstWebrtcDsp-struct"></a><h3>GstWebrtcDsp</h3>
<pre class="programlisting">typedef struct _GstWebrtcDsp GstWebrtcDsp;</pre>
</div>
</div>
<div class="refsect1">
<a name="gst-plugins-bad-plugins-webrtcdsp.property-details"></a><h2>Property Details</h2>
<div class="refsect2">
<a name="GstWebrtcDsp--echo-cancel"></a><h3>The <code class="literal">“echo-cancel”</code> property</h3>
<pre class="programlisting">  “echo-cancel”              <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre>
<p>Enable or disable echo canceller, note that it will be disabled if no webrtcechoprobe has been found.</p>
<p>Flags: Read / Write / Construct</p>
<p>Default value: TRUE</p>
</div>
<hr>
<div class="refsect2">
<a name="GstWebrtcDsp--experimental-agc"></a><h3>The <code class="literal">“experimental-agc”</code> property</h3>
<pre class="programlisting">  “experimental-agc”         <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre>
<p>Enable or disable experimental automatic gain control.</p>
<p>Flags: Read / Write / Construct</p>
<p>Default value: FALSE</p>
</div>
<hr>
<div class="refsect2">
<a name="GstWebrtcDsp--extended-filter"></a><h3>The <code class="literal">“extended-filter”</code> property</h3>
<pre class="programlisting">  “extended-filter”          <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre>
<p>Enable or disable the extended filter.</p>
<p>Flags: Read / Write / Construct</p>
<p>Default value: TRUE</p>
</div>
<hr>
<div class="refsect2">
<a name="GstWebrtcDsp--gain-control"></a><h3>The <code class="literal">“gain-control”</code> property</h3>
<pre class="programlisting">  “gain-control”             <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre>
<p>Enable or disable automatic digital gain control.</p>
<p>Flags: Read / Write / Construct</p>
<p>Default value: TRUE</p>
</div>
<hr>
<div class="refsect2">
<a name="GstWebrtcDsp--high-pass-filter"></a><h3>The <code class="literal">“high-pass-filter”</code> property</h3>
<pre class="programlisting">  “high-pass-filter”         <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre>
<p>Enable or disable high pass filtering.</p>
<p>Flags: Read / Write / Construct</p>
<p>Default value: TRUE</p>
</div>
<hr>
<div class="refsect2">
<a name="GstWebrtcDsp--noise-suppression"></a><h3>The <code class="literal">“noise-suppression”</code> property</h3>
<pre class="programlisting">  “noise-suppression”        <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre>
<p>Enable or disable noise suppression.</p>
<p>Flags: Read / Write / Construct</p>
<p>Default value: TRUE</p>
</div>
<hr>
<div class="refsect2">
<a name="GstWebrtcDsp--probe"></a><h3>The <code class="literal">“probe”</code> property</h3>
<pre class="programlisting">  “probe”                    <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gchar"><span class="type">gchar</span></a> *</pre>
<p>The name of the webrtcechoprobe element that record the audio being played through loud speakers. Must be set before PAUSED state.</p>
<p>Flags: Read / Write / Construct</p>
<p>Default value: "webrtcechoprobe0"</p>
</div>
<hr>
<div class="refsect2">
<a name="GstWebrtcDsp--echo-suppression-level"></a><h3>The <code class="literal">“echo-suppression-level”</code> property</h3>
<pre class="programlisting">  “echo-suppression-level”   <span class="type">GstWebrtcEchoSuppressionLevel</span></pre>
<p>Controls the aggressiveness of the suppressor. A higher level trades off double-talk performance for increased echo suppression.</p>
<p>Flags: Read / Write / Construct</p>
<p>Default value: Moderate Suppression</p>
</div>
<hr>
<div class="refsect2">
<a name="GstWebrtcDsp--noise-suppression-level"></a><h3>The <code class="literal">“noise-suppression-level”</code> property</h3>
<pre class="programlisting">  “noise-suppression-level”  <span class="type">GstWebrtcNoiseSuppressionLevel</span></pre>
<p>Controls the aggressiveness of the suppression. Increasing the level will reduce the noise level at the expense of a higher speech distortion.</p>
<p>Flags: Read / Write / Construct</p>
<p>Default value: Moderate Suppression</p>
</div>
<hr>
<div class="refsect2">
<a name="GstWebrtcDsp--delay-agnostic"></a><h3>The <code class="literal">“delay-agnostic”</code> property</h3>
<pre class="programlisting">  “delay-agnostic”           <a href="/usr/share/gtk-doc/html/glibglib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre>
<p>Enable or disable the delay agnostic mode.</p>
<p>Flags: Read / Write / Construct</p>
<p>Default value: FALSE</p>
</div>
</div>
</div>
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